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Re: Railway time (Standard Time) undone once again in the United States.
Author: mook
Date: 03-07-2015 - 16:23
Continental US time zones: [www.worldtimezone.com]
DST is optional for states in the US. Arizona and Hawaii don't do it. So in winter Arizona is on MST, in summer it's on PDT. But if they do use DST everybody follows the same start and end dates.
There's a reason why the military and most aviation operations use Coordinated Universal Time (formerly known as Greenwich Mean Time; also known as Zulu). And why Flightaware show most things other than local airport data in Eastern Standard Time. Avoids time zone confusions. Do railroads running through Arizona just use Omaha or Fort Worth time for the same reason?
BTW, worldtimezone.com has an interesting map of sun time, which doesn't necessarily match any of the time zones. It was to avoid confusion with local sun times that railroads adopted standard time and time zones. Daylight Saving Time was a political invention that came later.
Allegedly DST saves energy - but in my experience it costs energy in places that are hot (like the California Central Valley) because you come home and turn on the a/c for the hottest part of the day (mid-afternoon, sun time) rather than an hour later (sun time) when the sun has dropped a bit. Not that either DST or ST matter much in a place like Fresno where the hottest part of the day is usually from about an hour before sunset to 2 hours after (frequently doesn't drop below 100F until after midnight) ...
DST is optional for states in the US. Arizona and Hawaii don't do it. So in winter Arizona is on MST, in summer it's on PDT. But if they do use DST everybody follows the same start and end dates.
There's a reason why the military and most aviation operations use Coordinated Universal Time (formerly known as Greenwich Mean Time; also known as Zulu). And why Flightaware show most things other than local airport data in Eastern Standard Time. Avoids time zone confusions. Do railroads running through Arizona just use Omaha or Fort Worth time for the same reason?
BTW, worldtimezone.com has an interesting map of sun time, which doesn't necessarily match any of the time zones. It was to avoid confusion with local sun times that railroads adopted standard time and time zones. Daylight Saving Time was a political invention that came later.
Allegedly DST saves energy - but in my experience it costs energy in places that are hot (like the California Central Valley) because you come home and turn on the a/c for the hottest part of the day (mid-afternoon, sun time) rather than an hour later (sun time) when the sun has dropped a bit. Not that either DST or ST matter much in a place like Fresno where the hottest part of the day is usually from about an hour before sunset to 2 hours after (frequently doesn't drop below 100F until after midnight) ...
